The present invention relates to a device and method for heating a substrate, and a method for treating a substrate.
In a heating device in which a heat treatment of a substrate is performed, it is required for a gas stream to be produced under an upper plate in order to avoid gas or fine particles produced during the heating from deposition on the upper plate. Conventionally, there has widely been used a method in which gas is introduced from the surrounding area of a to-be-treated substrate and discharged upwardly through the middle portion of the upper plate. In this method, however, there arises a problem that a device is thick as a whole.
Further, in a conventional heating device, a heat diffusion plate for transmitting heat of a heater to a to-be-treated substrate is provided in a lower housing equipped with the heater and uniform heating on the surface of the lower housing is realized by making a thickness of the heat diffusion plate as thick as about 15 mm. There arises a problem, however, since while the heating is improved in uniformity when the heat diffusion plate is thick, heating responsibility is deteriorated. In order to improve heating responsibility, it is only required that the heat diffusion plate is thin. However, when the heat diffusion plate is thin, it is hard to realize uniform heating.
Division of a heater has been proposed in order to attain good heating uniformity (for example, see Jpn. Pat. Appln. KOKAI Publication No. 4-239120). In this proposal, however, no consideration is given to an influence of a gas stream under the upper plate. Therefore, good heating uniformity all over a substrate surface is hard to be attained.
Further, some examples have been found in the CVD process from the viewpoint of temperature correction of a gas stream (for example, Jpn. Pat. Appln. KOKAI Publication Nos. 9-237674 and 4-325683). However, these examples are proposed for realization of a uniform reaction of a raw material gas above a to-be-treated substrate. Accordingly, the teachings are hard to give a solution for good heating uniformity all over a substrate surface.
On the other hand, high precision is required in uniformity of heat supply to a substrate in a heating step after a chemical amplified type resist coated on a substrate is subjected to exposure. When a chemical amplified type resist is used, an acid diffusion reaction which occurs in a heating step progresses at a low speed even in room temperature immediately after the exposure. In a conventional heating method, such a problem as occur by an acid diffusion reaction has not been able to be solved.
As mentioned above, in a conventional heating device, it has been hard to attain good heating uniformity all over a substrate surface. Further, conventionally, it has also been hard to solve a problem occurring by an acid diffusion reaction after resist coating.